Replace lodash with es-toolkit to remove deprecated dependency and CommonJS optimization bailouts

[denatys]

Closes #253

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Note

Medium Risk
Swaps a foundational utility dependency (lodash) for es-toolkit/compat across schema modification and v0 form logic, which could introduce subtle behavioral differences in merge*, get/set, and array handling. Changes are broad but mostly mechanical and covered by updated tests/lockfiles.

Overview
Replaces lodash with es-toolkit/compat throughout the codebase (both v2 src/modify-schema.ts and the v0 implementation), updating all imports for common helpers like merge, mergeWith, get/set, difference, etc., and removing lodash/@types/lodash from manifests.

Dependency plumbing and tests were adjusted: lockfiles now include es-toolkit, v0 package.json/package-lock.json are updated, and a couple test fixtures were tweaked (e.g., merge({}, …) call sites and a minor expected-schema shape change in modify.test.js) to align with the new utility behavior.

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[denatys]

@sandrina-p @danielcardoso5 please review

[sandrina-p]

Hi @denatys, thanks for your MR! We'll review this later in the week, max early next one. :)